1. Field of the Invention
The invention relates to a method of performing a statistical test on a device or radio channel.
2. Related Technology
From WO 02/089390 A1 a test method to decide pass or fail over statistical tests is known. The applicability however is restricted. The elementary step has two outcomes: bit error/correct bit or lost packet/received packet or limit violated/limit met.
The following is an example of an application, where this test cannot be applied. In HSDPA (High Speed Downlink Packet Access) data packets are transmitted from the base station to the mobile station. The signal/noise ratio S/N is varying as function of time as shown in FIG. 1. The user-data throughput shall exceed a specified limit. The packets are transmitted equally spaced in time. Due to the mobile radio channel a portion of the packets can be received correctly, another portion is lost. As the lost packets occur irregularly, throughput is a statistical parameter under test. If the packets all carry the same quantity of user bits, the user-data-throughput can be statistically treated with the state of the art statistical approach. However, in HSDPA the user data in the packets have different quantities. For example packets b with 2 kbits user data are used in periods with high channel quality (high S/N) and packets a with only 1 kbits user data are used in periods with poor channel quality (low S/N) as shown in FIG. 1. The different packets a and b are received, or get lost, irregularly according to the irregular radio channel. Therefore the state of the art approach is not applicable, as the possible outcomes with respect to user data are multiple.